Cilium

 

• Cilium operates at L3/L4 to provide trasitional networking and security services
• It also works at L7 to provide application level servies like gRPC, HTTP, Kafka
• Cilium inserts itself in the kernel at
  • Network IO
  • Application Sockets and Tracepoints to implement security and visibility.
• Intelligent Routing
  • Cilium can do more intelligent routing other than opening or blocking a port
    • Allow all HTTP requests with method GET and path /public/.*. Deny all other requests.
    • Allow service1 to produce on Kafka topic topic1 and service2 to consume on topic1. Reject all other Kafka messages.
    • Require the HTTP header X-Token: [0-9]+ to be present in all REST calls.
    • More examples of policies at https://docs.cilium.io/en/stable/policy/#layer-7
• Service to Service Communication